From soarGFS to soarV2

The association Club Soaringmeteo intends to replace soarGFS with soarV2 in 2024. We would like to invite you to use soarV2 instead of soarGFS and let us know any concern you may have. This page explains the motivation behind this decision, and describes the differences between both tools. A more detailed documentation of soarV2 is available online by clicking to the “?” at the bottom right of the page soarV2.

Why replace soarGFS?

With about 100,000 visits per year, soarGFS is a tool that is beneficial to thousands of soaring pilots. Why do we want to change something that works?

As it is explained in the page Support Soaringmeteo, soarGFS is the creation of the passionate, self-taught pilot Jean Oberson. Although soarGFS was developed more than 10 years ago, it is still very useful to soaring pilots. Similarly, soarWRF is used by a growing number of visitors. This is impressive, congratulations to Jean Oberson!

The team of Soaringmeteo volunteers would like to improve further the tools soarGFS and soarWRF: decrease the CPU usage, simplify the user experience, expand the areas covered by the forecasts, reduce the maintenance costs, etc. Unfortunately, maintaining and evolving the software written 10 years ago is hard. Therefore, we decided to rewrite it from scratch. This will allow us to perform the desired improvements more easily while decreasing the risk of introducing bugs and without having to scale up our server infrastructure.

SoarV2 is an open source software, and your contributions are welcome!

Main benefits of soarV2

The main benefits of soarV2 compared to soarGFS are the following:

• soarV2 uses the model GFS with a resolution of 25 km versus 50 km for soarGFS, and the area covered by the forecast is much wider.
• soarV2 shows a forecast for 9 days versus 7 days for soarGFS.
• soarV2 computes the speed of thermals in m/s because this is what soaring pilots are used to, instead of showing the raw values of the sensible heat flux in W/m² like soarGFS does.

Default view

By default, the main view soarV2 is similar to the “aerological map” of soarGFS:

In both cases, the color of each point of the map shows the thermal soaring conditions (ThQ in soarGFS, XC flying potential in soarV2). The main differences are the following:

• The number of points in the map is significantly higher in soarV2. This is due to the fact that the underlying model has a resolution of about 25 km (instead of 50 km for soarGFS).
• The wind speed and direction are also shown by default on soarV2. You can hide the wind or switch to numerical values by clicking to the “layers” button at the bottom right of the screen.
• The colors of the points are not always exactly the same between soarGFS and soarV2. This is because the computation for the thermal quality is slightly different in both tools.
• The time is displayed according to your local timezone in soarV2 whereas it is displayed according to the Coordinated Universal Time (UTC) in soarGFS.

Meteograms

In soarV2, when you click to a location on the map a tooltip shows additional information as well as a button to display a meteogram for this location.

In both cases, the meteograms show the forecast for the next days at the selected location. Overall, both tools show similar information (thermal quality, cloud cover, boundary layer depth, wind speed and direction at various elevation levels, atmospheric pressure, rainfalls, etc.), but the layout is a bit different. The main differences are the following:

• The forecast covers 7 days in soarGFS whereas it covers 9 days in soarV2.
• In soarGFS, the cloud cover is shown by a pie chart indicating the total cloud cover, whereas soarV2 shows the cloud cover at various elevation levels with gray strips (the wider the strip, the more the cloud cover). The relative insolation is not shown in soarV2 because this data is too approximate.
• In soarGFS, we show the wind speed and direction at three elevation levels, whereas in soarV2 we show them at various elevation levels. In soarV2, you can show the numerical values for the wind speed instead of the wind barbs by clicking to the “layers” button at the bottom right of the screen, and then “Numerical values”.
• In soarGFS, we show the altitude of the convective clouds base with a numerical value, whereas in soarV2 we show them graphically.
• In soarGFS, we provide numerical values for the isotherm 0°C and the atmospheric pressure, whereas in soarV2 we show them graphically (the black curve and the red curve, respectively).
• In soarGFS, we show the temperature of the ground and the dew point temperature with numerical values, whereas in soarV2 we show them in the bottom graph.

Additionally, soarV2 shows the convective updraft velocity (below the XC potential, on the line that starts with “m/s”).

Sounding diagrams

The main differences are the following:

• soarGFS provides numerical values for the lapse rate, whereas in soarV2 we use a color code to indicate whether the atmosphere is stable (black and purple) or instable (orange and yellow).
• In soarGFS we only provide a numerical value for the wind direction, whereas in soarV2 we show the wind direction with an arrow. In soarV2, you can show the numerical values for the wind speed instead of the wind barbs by clicking to the “layers” button at the bottom right of the screen, and then “Numerical values”.
• In soarGFS, we show the cloud cover with pie charts at the following elevation levels: boundary layer, low-level clouds, middle-level clouds, high-level clouds, and total cloud cover. In soarV2, we show the cloud cover with the gray strips at the right of the diagram, at many elevation levels. The wider the strip, the more the cloud cover.
• Several variables (CAPE, CIN, irradiance, latent sensible heat, atmospheric pressure) are provided in soarGFS only.

Additionally, soarV2 shows the convective updraft velocity (in m/s).

Other differences

Here are some other differences between soarGFS and soarV2:

• There are no pressure difference diagrams in soarV2.
• There are no “text forecasts” in soarV2.
• The user interface is available only in English in soarV2.

If these features are important for you, please file an issue or email us.